LOANS HELD FOR INVESTMENT, Age Analysis on Accruing Past-due Loans and Nonaccrual Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	$ 2,788,640	$ 2,748,081
Nonaccrual	5,148	5,802
Nonaccrual with no ACL	3,220
Nonaccrual mortgage loans held for sale	0	0
30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	7,048	5,951
90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	2,432	1,987
Commercial Real Estate [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	926,018	919,358
Nonaccrual	79	0
Nonaccrual with no ACL	79
Commercial Real Estate [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	2,236	342
Commercial Real Estate [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	19	27
Commercial [Member] \| Specialized [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	315,473	327,513
Nonaccrual	36	38
Nonaccrual with no ACL	0
Commercial [Member] \| Specialized [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	1,042	25
Commercial [Member] \| Specialized [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	13	13
Commercial [Member] \| General [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	510,917	484,783
Nonaccrual	3,671	3,357
Nonaccrual with no ACL	3,141
Commercial [Member] \| General [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	753	1,451
Commercial [Member] \| General [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	74	60
Consumer [Member] \| 1-4 Family Residential [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	485,396	460,124
Nonaccrual	1,326	1,356
Nonaccrual with no ACL	0
Consumer [Member] \| 1-4 Family Residential [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	1,285	1,389
Consumer [Member] \| 1-4 Family Residential [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	2,011	1,653
Consumer [Member] \| Auto Loans [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	321,309	321,476
Nonaccrual	0	0
Nonaccrual with no ACL	0
Consumer [Member] \| Auto Loans [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	335	707
Consumer [Member] \| Auto Loans [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	94	85
Consumer [Member] \| Other Consumer [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	81,413	81,308
Nonaccrual	36	37
Nonaccrual with no ACL	0
Consumer [Member] \| Other Consumer [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	251	1,487
Consumer [Member] \| Other Consumer [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	221	149
Construction [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	148,114	153,519
Nonaccrual	0	1,014
Nonaccrual with no ACL	0
Construction [Member] \| 30-89 Days Past Due [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	1,146	550
Construction [Member] \| 90 Days or More Past Due and Still Accruing [Member]
Age Analysis on Accruing Past-due Loans and Nonaccrual Loans [Abstract]
Past Due	$ 0	$ 0

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